I was travelling from Karachi to Lahore to stay at relative’s place, they were facing load shading of 6 to 8 hours daily so due to nature of my work it was necessary for me to have a backup plan like an inverter or UPS as I need to stay online and during those days temperature was a bit hot in Lahore so I decided to make a power backup that can fulfill my needs and provide me backup for 2 to 3 hours at-least.

My requirements were:

1 – To charge a laptop

2 – To charge mobile phones and powerup a Charji or Zong internet device(3 phones)

3 – Must have a fan

4 – Must have enough light to light-up a room


I have to keep it with me so it must be small in size and light in weight. By keeping all these things in mind I started working on a solution.


External Accessories

External accessories can be connected with this power house to power-up additional stuff like:

1 – 96 LED Extra Bright Light (equals to 3 to 4 energy savers)

2 – Car mobile charging dock for direct 12V mobile charging

3 – Routers, sound systems can be connected with output

4 – Solar charger can be connected to charge battery via solar input


Backup Timings

Charging Time : 2 Hours to 3 Hours max

Output Timings :

Laptop Charging + Fan + LED = 1.6 to 2 Hours max

Fan + LED = 3 to 3.5 Hours

Laptop Charging = 3 to 3.5 Hours

Laptop Charging + Fan + Extra Bright LED = 1.5 Hours max

Fan + Extra Bright LED = 3 to 3.5 Hours



The DC UPS and AC Inverter I have designed is able to handle load of 200 to 250 Watts, it can power a pedestal fan and television at once, it can be powered by external battery and it has ability to charge external battery upto 80Ah. Its fully automatic and its charger will auto shut down when battery gets full.


1 – Fully Automatic Charger, ability to handle upto 80Ah battery

2 – Fully Automatic Switching

3 – Similar to Sine-Wave output, PWM based output protects load from over voltage

4 – Direct DC Output of 12V

5 – Heat protection, Overload protection, Fuse protection, Short circuit protection





I have purchased a 12V battery charging box, in now a days small chargers with fan are available in market (they have many disadvantages so they are not of my use, for example silver winded cheap 12V transformer based non automatic charger that destroys battery life, and small 5A battery that can’t handle the load for long) so I have purchased box of that charger and decided to build everything by my own.




There are many ways to charge a 7Ah battery like we can use a 12V / 1A or 500ma transformer based charger but it wont be automatic and it will destroy battery life quickly, and it wont be able to charge external batteries therefore I have purchased a Smart charger, that is fully automatic with several features like wrong polarity protection and short circuit protection. It has ability to charge upto 80Ah external battery as well and it was so much light weight as compare to a transformer therefore it was the best choice for my project.


I have used many inveters so far but most of those cheap inverters are not able to handle the load, till I came to know about Suoer Power Inverters, these are high quality inverters with many features like short circuit protection, under voltage auto cut-off, near to sine-wave output, heat protection and a lot more. It also provides full ouput (although it can handle the load of 500W but to be on safe side never connect load over 250Watts)




To make everything automatic relay is the simplest and best choice therefore I have purchased a 14 pin 220V operated relay, you can also use 11 pin 220V relay for same protect.



These cooling fans are commonly available in Karachi electronics market, these fans are outdated and expired fans taken out from server machines and power supplies, 4 of these fan can provide good enough air to provide air through for 2 to 4 persons.

LED Light


12V small LED circle boards are commonly available in Karachi Electronics market and can be purchased for 20 to 25 rupees. These LEDs provides 6 to 8W output enough to lightup a room.


Now after having all the stuff I have just connected everything as per given wiring guide.



I have started assembling by fitting battery in the box, I have used shettring strips (can be purchased from hardware store) to prepare battery clamp (fitting)




After fitting the battery I have fit the relay in interver.


After fixing the relay, I have made some hole in box to fit the inverter in the box.


After that I have fitted a power socket outside the box for that I have purchased normal electrical extension available in market for 150 rupees.



After that I place charger in the box and connected everything with each other as per above given wiring guide, after that I have connected the plug into AC to test the charging status and it was working fine.


After that I place the inverter on/off switch outside the box and prepare its wires, also place LED outside box and connected its wires


After that I complete the wiring of fans and placed fan and external power switch outside the box near fan (can be seen in video) and completed the remaining wiring. I have also made some holes for air in box body.


Damn after 8 hours of hardwork my power house was ready to use. Now you can made the same inverter / ups in your house very easily by few hours of working.


Cost of this project:

Box : 200 Rupees

LED, Switches, Wires, Extension, Nuts, bolts, and other stuff = 500 Rupees

Battery 7Ah = 1200 Rupees

Full automatic 5A charger = 1000 Rupees

Suoer Power Inverter = 1800 Rupees

Server Fans = 600 Rupees


Total Cost of project = 5300/= Rupees – Equals to $53